Clearance-space grinding-disk.



P ATENTED MAR. 27, 1906 No. 816,461V

G. GORTON. ULEARANGE SPA GB @BINDING DISK.v

APPLICATION I'LED 13116.22. 1904.

,zus-Ixix Unirnn s'rArns PATENT orrion. 1

Groen eoRToN, or RACINE, wisconsin;

CLEARANCE-SPACE GRlNDlNG-DISK.

Specification of Letters Patent.

Patented March 27,1906.

Applioatien filed December 22, 1904. Serial No. 237.971.

To all whom it may con/cern:

Be it known that I, GEORGE GoRToN, a

` citizen of the United States, residing at Racine, Racine county,Wisconsin, have invented certain new and useful Improvements inClearance-S ace Grinding-Disks; and I do hereby dec are the followingtobe a full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same. p l

This invention relates to certain improvements in abrading-sheets, andmore particuamong others within the spirit or scope of my invention,Figure l is a plan view of a `grinding-disk or abrading-sheetconstructed 1n laccordance with my invention. Fig. 2 is across-sectional view, on an enlarged scale. Fig. 3 is a section onanexaggerated scale, showing a different formation of abradingsurface.

In the drawings, 2 is a sheet of pa er, fabric, or other suitable,usually iiexib e, material. One face of this sheet is usually lain ornot 'covered with abrading material,w ereby said plain face of the sheetcan be glued or otherwise secured to the rotary head or disk Vof agrinding or other machine, althou h said abrading-sheets can be securedon cy inders or bufllng-wheels or can be employed in the form of endlesstraveling bands `or otherwise,

as may be desired. The opposite face of the sheet is provided with theabrading-face, which is .formed thereon by applying li uid "glue orother adhesive to the sheet and t en sprinkling or otherwise depositingthe desired .quantity of grit on the deposit of glue,

' so that the grit is, in effect', taken up by the adhesive, which on`hardening forms a binderfor the Grit and secures the abradin -surface tothe sheet. Any suitable gradeo grit can be used in any desired quantityto form the abrading-surface the desired thickness. The abrading-surfaceof each disk or sheet is usually of approximately the same thicknessthroughout-that is, the working face of the abrading-surface of therinding-disk is preferably iiat and in one p ane. material or surface 3of the disk practically forms one or a single sheet or surface. In otherwords, it is not broken up into separate ortions or areas, but clearanceis provided or by a great plurality of isolated suitablydistributedsmall blank or uncovered or nony working4 spots or recesses 4, which canbe formed in the abrading-surface by any4 suitable means or by asuitable step or steps in the process of manufacturing thegrinding-disks. The single or continuous-abrading-surface isinactive, sofar as grinding or working is 1 concerned, at the severalclearance-spots 4,

whether said spots be entirely blank, of grit, or whether the floors ofsaid s ots are lentirely below the working face o the abrading-surface.In other words, working abrading-mate'rial faces are lacking at theseiso-V lated spots, and hence said spots provide for" clearance as therefuse and grit worn from the work being ground and from theabradingsurface ind ready escape into said spots.

Each clearance-spot can be of any suitable shape or form, although Iprefer spots of the general outline shown and that all the spots of asheet be similar in form and dimensions, although I do not wish to solimit my invention. The clearance-spots can be arranged or distributedin any suitable manner, and I do not wish to limit myself to a uniformor even distribution thereof in the single continuous abrading-materialsurface, which is unbroken except for s aid spots, as said surface isnot by said spots divided into areas or working portions. I usuallyarrange the spots equally spaced apart and distributed throughout thesingle sheet or layer of abrading material, and hence I usually lay out.the spots in parallel equally-spaced. rows intersected at right'angle'sby parallel equallyspaced rows. I

When the grinding-disks are in the form of circular sheets with acentral perforation, asy shown, Iusually form the annularabradingsurface with annular outer and inner narrow portions lor margins5, which are not formed withtheclearance-spots. This peculiar formationwith the narrowl annular non-clearance inner and outer edge portionsadds to the The abrading IOO IIO

durability of the edge portions or margins of the abrading-suriace; butI do not Wish to limit 4other features of my invention thereto.

I show in an exaggerated manner in Fig. 3 a sheet 6, which can be formedof cloth or fabric having the continuous Working abrading-material sheetor surface 3, With clearance spots or non-Working blanks 7, Jformingrecesses into which the refuse can escape, thereby providing forclearance. The sheet 6 has thin non-Working layers of grit forming thedepressed i'loors of these spots, so that the spots 7 are,I in effect,formed by small concavities or refuse-receiving recesses.

I have found b experience that materially-increased e ciency anddurability in clearance-space abrading-s-urfaces is attained byemploying practically a Single or continuous sheet or one layer ofabrading material, as distinguished from se arated or distinct sheets,layers, or areas o abrading material or Working faces and by formingisolated clearance-spots or non-Working blanks in this practicallycontinuous layer or sheet of abrading material. The spots provide forsuch free and rapid clearance as may be necessary, and et theabrading-surface is not materiall Weahened` or reduced by the spots, asthe a rading surface is bound together throughout into one sheet orlayer an comprises a maximum quantit of abrading-grit.

abrading-surface l find that my improve possesses quallties of greatendurance and also attains a very high eiiiciency, thereby effectingincreased econorn" in the use of clearance-space grinding-dis s.

' lDivided and blank clearance-space abrading-surfaces are, broadly,very old in various.

`struction show-n.

arts and, broadly considered havbeen Well known to those skilled in theart for many years; but it is the object of my invention to produce agrinding-disk of higheiciency and durability and capable of -beingproduced at a low cost, whereby clearance-space grindingdisks can begenerally used in practice on an economical basis.

It is evident that various modifications might be resortedtowitlout.departin from the spirit and scope of my invention. l ence I do notWish to limit myself to the exact con- Havingthus described myinvention, What l I claim 1sand consisting of a layer ofadhesive-andgrit formed With a multiplicity of isolated none.

working clearance-spots distributed through out said surface, eachsurrounded by said abrading-surface, whereby all portions of said layerare bound or connected together, substantially as described.

2. A grinding-sheet consistin of a flexible sheet having a layer 3 ofabra ing material secured Ona face thereof and formed with amultiplicity of isolated blank clearance-spots 4, distributed throughoutsaid layer between the margins thereof, substantially as de. y

scribed.

In testimony whereof I aiiix my in presence of tWo Witnesses.

GEORGE GORTON.

signature Witnesses:

CHRISTOPHER C. GITTINGS,

MATTIE E. PALMER'.

